PSR-600 volume too loud to sleep with!

Status
Not open for further replies.

newmission

Member
Joined
Jun 16, 2008
Messages
25
Location
Oregon, OH
I did a quick search and read a few posts, but nothing on the topic was found. Forgive me if the issue has been brought up previously.

With that said, is it just me or does anyone else notice a volume "jump" when in the first quarter turn area? My wife and I like the noise of the radio while sleeping but we just switched from a pro96 to the 600 and there's just no sweet spot. Seems like right around a quarter turn in the volume knob, it jumps from too soft to hear to too loud to sleep with.

Now I have read through the manual and fiddled with all the menus, but haven't found any sort of gain adjustment. Does any such adjustment exist? I guess I could always use an external speaker, but I'm still worn out from convincing my wife to upgrade the radio. :)
 

sjlamb

Member
Joined
May 27, 2007
Messages
882
Location
Sarasota County, FL
The issue is the simple end result of GRE inexplicably having used a linear taper volume control as opposed to using the proper AUDIO taper control. The fix would be to find a direct replacement control of the same rating (likely 10K ohms) BUT, with an audio taper (easier said than done).
 

dougr1252

Member
Joined
Sep 29, 2007
Messages
264
My solution was to order a new one from RS parts ($10 I think) and swap it out. Now I have a good one.
 

garys

Member
Premium Subscriber
Joined
Jun 13, 2002
Messages
4,908
Location
Eastern MA
I've noticed the same thing, although I use the PSR600 at work, not in the bedroom. Additionally, the "feel" of the volume control is terrible. The volume control moves far too easily for use in a mobile environment. The feel of the Uniden DMA scanners is far better, as is the audio taper. I'm stick with what the fleet manager buys, but for the sake of PSR users, I hope GRE fixes this in future scanners.
 

newmission

Member
Joined
Jun 16, 2008
Messages
25
Location
Oregon, OH
Not to hi-jack your thread, but I think the real issue is you've found a wife that likes the scanner noise. Congrat's! :D
Hey, the Lord works in mysterious ways. :)

Her grandmother had one going 24/7 for years (answers the question if it's ok to leave 'em running).

We had this sound machine but I always got annoyed when it came to the loop.
 

hfxChris

Member
Database Admin
Joined
Aug 18, 2007
Messages
1,337
Location
Dartmouth, Nova Scotia
The issue is the simple end result of GRE inexplicably having used a linear taper volume control as opposed to using the proper AUDIO taper control.
And the sad thing is, they've been doing that for years. I was really hoping when GRE released the newest generation of scanners, they would finally put in an appropriate volume pot, but I guess not.
 

GTO_04

Member
Premium Subscriber
Joined
Mar 10, 2004
Messages
1,844
Location
Noblesville, IN
My Pro-197 (PSR-600 clone) has the same issue. It was so annoying that I retired it to the kitchen
and bought a 996XT for the bedroom. It's too bad because othewise the 197 is a fine scanner.

It takes a real fine adjustment of the volume control not so it's not too loud or too soft. Usually it is around the 9:00 position on the dial.

It is puzzling why they have not addressed this issue when the fix is very easy!

I don't seem to have this problem on my PSR-500

GTO_04
 

KCChiefs9690

CQ DX
Joined
Mar 20, 2004
Messages
1,794
Location
Lewis Center, OH
My Pro-197 (PSR-600 clone) has the same issue. It was so annoying that I retired it to the kitchen
and bought a 996XT for the bedroom. It's too bad because othewise the 197 is a fine scanner.

It takes a real fine adjustment of the volume control not so it's not too loud or too soft. Usually it is around the 9:00 position on the dial.

It is puzzling why they have not addressed this issue when the fix is very easy!

I don't seem to have this problem on my PSR-500

GTO_04
I can second that about the PSR-500, the volume is easy to adjust for comfortable listening in bed. I have a PRO-2055 (which I believe is also made my GRE), and it has the same sloppy volume control that the PSR-600 has.
 

sjlamb

Member
Joined
May 27, 2007
Messages
882
Location
Sarasota County, FL
It is puzzling why they have not addressed this issue when the fix is very easy!

GTO_04
I'm guessing that they are the proud owners of a couple skillion linear taper pots (that also happen to be cheaper).

A switch to an audio taper pot would give you a gradual volume increase along the entire turn radius on those 600's. The trick will be finding one that is an exact physical switch out with the OEM pot. It's probably either a 50K or 10K pot.
 

DonS

Member
Joined
Jun 17, 2003
Messages
4,106
Location
Franktown, CO
An audio pot wouldn't fix the volume "jump" described by the O.P. This is somewhat supported by other peoples' (posters above, plus me) experience with these scanners: some seem smooth (though not "linear" according to our ears), while others seem "jumpy".

I'd suggest a few squirts of tuner cleaner before trying to replace the linear pot.

EDIT: On my PSR-600 and PRO-106 I can, with very careful adjustment of the volume control, get any volume I want through the entire range. It's not "linear" (pot position vs. my ears' perception), of course, but there are no "jumps" that I can perceive.
 
Last edited:

newmission

Member
Joined
Jun 16, 2008
Messages
25
Location
Oregon, OH
I majored in electronics, but just can't break myself to swap a brand new switch on a sizable investment. But might be willing to swap the speaker to something with a greater resistance. Anyone thought/tried that?
 

sjlamb

Member
Joined
May 27, 2007
Messages
882
Location
Sarasota County, FL
An audio pot wouldn't fix the volume "jump" described by the O.P. This is somewhat supported by other peoples' (posters above, plus me) experience with these scanners: some seem smooth (though not "linear" according to our ears), while others seem "jumpy".

I'd suggest a few squirts of tuner cleaner before trying to replace the linear pot.

EDIT: On my PSR-600 and PRO-106 I can, with very careful adjustment of the volume control, get any volume I want through the entire range. It's not "linear" (pot position vs. my ears' perception), of course, but there are no "jumps" that I can perceive.
I respectfully disagree. While a shot of tuner cleaner often resolves an oxidized or otherwise dirty potentiometer; the OP's (and many others before him) description of the "touchy" volume control on the PSR-600 perfectly describes the difference between using an audio taper vs. a linear taper in a volume control. In relevant part:

Linear and Audio Taper

"If you tried to use a linear taper pot as a volume control you would be most unhappy with its performance. The sound level would go from nothing to almost full volume in about the first ten degrees of rotation and the rest would have almost no audible effect. "

To read the full article, including technicial data: http://www.angelfire.com/electronic/funwithtubes/Amp-Volume.html
 

sjlamb

Member
Joined
May 27, 2007
Messages
882
Location
Sarasota County, FL
I majored in electronics, but just can't break myself to swap a brand new switch on a sizable investment. But might be willing to swap the speaker to something with a greater resistance. Anyone thought/tried that?
Your alternative to switching to the correct type of volume control would be to hook it up to an external speaker that has it's own volume control on the speaker itself. Pump the unfettered 600 audio into the speaker and control the actual listening volume directly from the speaker. Problem solved...

SP-170F from ScannerMaster:
 

Attachments

Last edited:

DonS

Member
Joined
Jun 17, 2003
Messages
4,106
Location
Franktown, CO
Linear and Audio Taper

"If you tried to use a linear taper pot as a volume control you would be most unhappy with its performance. The sound level would go from nothing to almost full volume in about the first ten degrees of rotation and the rest would have almost no audible effect. "

To read the full article, including technicial data: http://www.angelfire.com/electronic/funwithtubes/Amp-Volume.html
Perhaps my PSR-600 and PRO-106 are oddities of manufacturing. Neither of my scanners exhibit the behavior described above. My ears definitely hear significant differences in volume throughout the pots' travels.

My sound level meter hears differences, too. Listening to a local Wx channel (162.450MHz) with the meter 12 inches from, and parallel to, the front panel of the scanners, and with varying volume pot positions, the meter displays:
Code:
Pot Position        PSR-600      PRO-106
OFF (ambient)               50dB
   9:00              63dB         56dB
  12:00              78           69
   3:00              89           80
 Maximum             92           85
 

DonS

Member
Joined
Jun 17, 2003
Messages
4,106
Location
Franktown, CO
I also looked at my old alpha hardware for the PSR-500. It's a 50k logarithmic pot: on the side I measured after disconnecting the pot from the rest of the audio circuit, 9:00 is 850 ohms, 12:00 is ~8.7k ohms, and 3:00 is ~35k ohms.

I have not de-soldered (and am not going to de-solder) my PSR-600 and PRO-106 pots to make such measurements; I'm satisfied with the audio level measurements and "ear experience" described above.

If people have linear pots in their scanners, it's a parts supply or manufacturing problem, not an inherent design problem. (If "everyone" had linear pots, "everyone" would probably return the scanners).
 

tglendye

Member
Joined
Jun 15, 2002
Messages
1,762
Location
Virginia
My Pro-197 (PSR-600 clone) has the same issue. It was so annoying that I retired it to the kitchen
and bought a 996XT for the bedroom. It's too bad because othewise the 197 is a fine scanner.

It takes a real fine adjustment of the volume control not so it's not too loud or too soft. Usually it is around the 9:00 position on the dial.

It is puzzling why they have not addressed this issue when the fix is very easy!

I don't seem to have this problem on my PSR-500

GTO_04
I just got a Pro-197 when RS put them on sale. I am having the same issue with the volume "jumping" with a slight adjustment of the knob. I remembered this thread and searched it to review what was said. I also have a PSR-500 and do not have this issue.

Todd
 
Status
Not open for further replies.
Top